1. Field of Invention
This invention pertains generally to packing materials and, more particularly, to a machine and method for making air-filled packing cushions.
2. Related Art
Air-filled pillows or cushions are currently used as a packing material and void filler in shipping cartons and the like. Such cushions typically have two layers of plastic film material which are sealed together to form chambers that are filled with air. The cushions are usually made in continuous strings, with perforations between successive ones of the cushions so they can be torn apart.
Although very light in weight, air-filled cushions do take up a substantial amount of space, and to reduce the volume of material which must be shipped and stored, such cushions are commonly made at or near the point of use. To avoid the need for packers and shippers to have large, complex cushion making machines in their facilities, suppliers of air-filled packing cushions provide their customers with prefabricated film materials in which the major seals and perforations have already been formed. Those materials usually wound into rolls or folded into boxes for shipment and storage.
Packers and shippers who use the prefabricated film materials are also provided with relatively simple, inexpensive machines for inflating and sealing the materials to complete the cushions at or near the point of use. Examples of such machines are found in U.S. Pat. No. 6,209,286 and in copending Ser. Nos. 09/638,843 and 09/717,782, the disclosures of which are incorporated herein by reference.